Hollow fiber membrane module repair method and hollow fiber membrane module
This repair method for a hollow fiber membrane module is a method for repairing a leaking section occurring in the hollow fiber membrane module, the repair method having a repair step for using a repair adhesive that hardens due to a composite curing function that comprises a moisture-curing function and a photo-curing function, to repair the leaking section.
1. A method of repairing a leakage region occurring at a hollow fiber membrane module, the method comprising
contacting the leakage region with a repair agent that comprises a moisture curing function, a light curing function, a cyanoacrylate based component, a polymerizable silicon-containing component, and a photopolymerization initiator while the hollow fiber membrane module is wet, and
curing the repair agent with moisture contained in a hollow fiber membrane of the hollow fiber membrane module and light,
wherein the cyanoacrylate based component is present in an amount of 85 to 90 mass % relative to 100 mass % of the repair agent,
a wherein the polymerizable silicon-containing component is vinyltrimetoxysilane,
wherein the repair agent has a viscosity of between 10 and 3000 mPa·s at room temperature,
wherein the hollow fiber membrane of the hollow fiber membrane module has a water content of 30 mass % or more and 90 mass % or less when the contacting is performed, and
wherein the cyanoacrylate based component comprises one or more cyanoacrylate monomers selected from the group consisting of methyl cyanoacrylate, ethyl-2-cyanoacrylate, propyl cyanoacrylate and a combination thereof.
2. The method of claim 1 , wherein the contacting is performed after detecting the leakage region by pressurizing gas into the hollow fiber membrane module in a direction along filtration of the hollow fiber membrane module or in a direction opposite to the filtration under a condition where the hollow fiber membrane module is immersed in water or an aqueous solution.
3. The method of claim 1 , wherein the leakage region is a defective place in a membrane surface of a hollow fiber membrane of the hollow fiber membrane module, and
the contacting comprises applying the repair agent to the defective place.
4. The method of claim 1 , wherein the repair agent has a viscosity of between 10 and 1000 mPa·s at room temperature before curing.
5. The method of claim 1 , wherein the repair agent has a viscosity of between 100 and 1000 mPa·s at room temperature before curing.
6. The method of claim 1 , wherein the photopolymerization initiator has a reaction wavelength between 100 and 400 nm.
7. The method of claim 1 , wherein the light is ultraviolet light.
8. The method of claim 1 , wherein the cyanoacrylate based component comprises ethyl-2-cyanoacrylate.